-- Модуль основан на коде модуля [[:en:Module:UnitTests|Module:UnitTests]] англоязычного раздела Википедии.
-- UnitTester provides unit testing for other Lua scripts. For details see [[Wikipedia:Lua#Unit_testing]].
-- For user documentation see talk page.
local UnitTester = {}

local frame, tick, cross
local result_table_header = '{| class="wikitable"\n|+ %s\n' ..
	'! scope="col" | \n' ..
	'! scope="col" | Тест\n' ..
	'! scope="col" | Ожидаемое значение\n' ..
	'! scope="col" | Фактическое значение '
local result_table_live_sandbox_header = '{| class="wikitable"\n|+ %s\n' ..
	'! scope="col" | \n' ..
	'! scope="col" | Тест\n' ..
	'! scope="col" | Фактическое значение\n' ..
	'! scope="col" | Песочница\n' ..
	'! scope="col" | Ожидаемое значение'

local result_table = { n = 0 }
local result_table_mt = {
	insert = function (self, ...)
		local n = self.n
		for i = 1, select('#', ...) do
			local val = select(i, ...)
			if val ~= nil then
				n = n + 1
				self[n] = val
			end
		end
		self.n = n
	end,
	insert_format = function (self, ...)
		self:insert(string.format(...))
	end,
	concat = table.concat
}
result_table_mt.__index = result_table_mt
setmetatable(result_table, result_table_mt)

local num_failures = 0

function first_difference(s1, s2)
    if s1 == s2 then return '' end
    local max = math.min(#s1, #s2)
    for i = 1, max do
        if s1:sub(i,i) ~= s2:sub(i,i) then return i end
    end
    return max + 1
end

local function return_varargs(...)
	return ...
end

function UnitTester:preprocess_equals(text, expected, options)
    local actual = frame:preprocess(text)
    if actual == expected then
        result_table:insert('| ', tick)
    else
        result_table:insert('| ', cross)
        num_failures = num_failures + 1
    end
    local maybe_nowiki = (options and options.nowiki) and mw.text.nowiki or return_varargs
    local differs_at = self.differs_at and (' \n| ' .. first_difference(expected, actual)) or ''
    result_table:insert(' \n| ', mw.text.nowiki(text), ' \n| ',
    	maybe_nowiki(expected), ' \n| ', maybe_nowiki(actual), differs_at,
    	"\n|-\n")
end

function UnitTester:preprocess_equals_many(prefix, suffix, cases, options)
    for _, case in ipairs(cases) do
        self:preprocess_equals(prefix .. case[1] .. suffix, case[2], options)
    end
end

function UnitTester:preprocess_equals_preprocess(text1, text2, options)
    local actual = frame:preprocess(text1)
    local expected = frame:preprocess(text2)
    if actual == expected then
        result_table:insert('| ', tick)
    else
        result_table:insert('| ', cross)
        num_failures = num_failures + 1
    end
    local maybe_nowiki = (options and options.nowiki) and mw.text.nowiki or return_varargs
    local differs_at = self.differs_at and (' \n| ' .. first_difference(expected, actual)) or ''
    result_table:insert(' \n| ',
		mw.text.nowiki(text1),													-- the tested template nowikied
		' \n| ',
		maybe_nowiki(expected),													-- the expected version
		highlight and ' \n|style="background: #fc0;"| ' or ' \n| ',				-- highlighted if test fail; not else
		maybe_nowiki(actual), differs_at,										-- the actual rendering using its own template styles if that is an option
		"\n|-\n")
end

function UnitTester:preprocess_equals_compare(live, sandbox, expected, options)
	local live_text = frame:preprocess(live)
	local sandbox_text = frame:preprocess(sandbox)

	local highlight_live = false
	local highlight_sandbox = false
	if live_text == expected and sandbox_text == expected then
		result_table:insert('| ', tick)
	else
		result_table:insert('| ', cross)
		num_failures = num_failures + 1

		if live_text ~= expected then
			highlight_live = true
		end

		if sandbox_text ~= expected then
			highlight_sandbox = true
		end
	end
    local maybe_nowiki = (options and options.nowiki) and mw.text.nowiki or return_varargs
    local differs_at = self.differs_at and (' \n| ' .. first_difference(expected, live_text) or first_difference(expected, sandbox_text)) or ''
    result_table:insert(
			' \n| ',
			mw.text.nowiki(live),
			highlight_live and ' \n|style="background: #fc0;"| ' or ' \n| ',
			maybe_nowiki(live_text),
			highlight_sandbox and ' \n|style="background: #fc0;"| ' or ' \n| ',
			maybe_nowiki(sandbox_text),
			' \n| ',
			maybe_nowiki(expected),
			differs_at,
			"\n|-\n"
	)
end

function UnitTester:preprocess_equals_preprocess_many(prefix1, suffix1, prefix2, suffix2, cases, options)
    for _, case in ipairs(cases) do
        self:preprocess_equals_preprocess(prefix1 .. case[1] .. suffix1, prefix2 .. (case[2] and case[2] or case[1]) .. suffix2, options)
    end
end

function UnitTester:preprocess_equals_sandbox_many(module, function_name, cases, options)
    for _, case in ipairs(cases) do
		local live = module .. "|" .. function_name .. "|" .. case[1] .. "}}"
		local sandbox = module .. "/песочница|" .. function_name .. "|" .. case[1] .. "}}"
        self:preprocess_equals_compare(live, sandbox, case[2], options)
    end
end

function UnitTester:equals(name, actual, expected, options)
    if actual == expected then
        result_table:insert('| ', tick)
    else
        result_table:insert('| ', cross)
        num_failures = num_failures + 1
    end
    local maybe_nowiki = (options and options.nowiki) and mw.text.nowiki or return_varargs
    local differs_at = self.differs_at and (' \n| ' .. first_difference(expected, actual)) or ''
    result_table:insert(' \n| ', name, ' \n| ',
        maybe_nowiki(tostring(expected)), ' \n| ',
        maybe_nowiki(tostring(actual)), differs_at, "\n|-\n")
end

local function deep_compare(t1, t2, ignore_mt)
    local ty1 = type(t1)
    local ty2 = type(t2)
    if ty1 ~= ty2 then return false end
    if ty1 ~= 'table' and ty2 ~= 'table' then return t1 == t2 end

    local mt = getmetatable(t1)
    if not ignore_mt and mt and mt.__eq then return t1 == t2 end

    for k1, v1 in pairs(t1) do
        local v2 = t2[k1]
        if v2 == nil or not deep_compare(v1, v2) then return false end
    end
    for k2, v2 in pairs(t2) do
        local v1 = t1[k2]
        if v1 == nil or not deep_compare(v1, v2) then return false end
    end

    return true
end

function val_to_str(v)
    if type(v) == 'string' then
        v = mw.ustring.gsub(v, '\n', '\\n')
        if mw.ustring.match(mw.ustring.gsub(v, '[^\'"]', ''), '^"+$') then
            return "'" .. v .. "'"
        end
        return '"' .. mw.ustring.gsub(v, '"', '\\"' ) .. '"'
    else
        return type(v) == 'table' and table_to_str(v) or tostring(v)
    end
end

function table_key_to_str(k)
    if type(k) == 'string' and mw.ustring.match(k, '^[_%a][_%a%d]*$') then
        return k
    else
        return '[' .. val_to_str(k) .. ']'
    end
end

function table_to_str(tbl)
    local result, done = {}, {}
    for k, v in ipairs(tbl) do
        table.insert(result, val_to_str(v))
        done[k] = true
    end
    for k, v in pairs(tbl) do
        if not done[k] then
            table.insert(result, table_key_to_str(k) .. '=' .. val_to_str(v))
        end
    end
    return '{' .. table.concat(result, ',') .. '}'
end

function UnitTester:equals_deep(name, actual, expected, options)
    if deep_compare(actual, expected) then
        result_table:insert('| ', tick)
    else
        result_table:insert('| ', cross)
        num_failures = num_failures + 1
    end
    local maybe_nowiki = (options and options.nowiki) and mw.text.nowiki or return_varargs
    local actual_str = val_to_str(actual)
    local expected_str = val_to_str(expected)
    local differs_at = self.differs_at and (' \n| ' .. first_difference(expected_str, actual_str)) or ''
    result_table:insert(' \n| ', name, ' \n| ', maybe_nowiki(expected_str),
    	' \n| ', maybe_nowiki(actual_str), differs_at, "\n|-\n")
end

function UnitTester:run(frame_arg)
    frame = frame_arg
    self.frame = frame
    self.differs_at = frame.args['differs_at']
    tick = frame:preprocess('{{Tick}}')
    cross = frame:preprocess('{{Cross}}')

    local table_header = result_table_header
	if frame.args['live_sandbox'] then
		table_header = result_table_live_sandbox_header
	end
    if self.differs_at then
        table_header = table_header .. '\n! scope="col" title="Различается на символе" | Разл. на'
    end

    -- Sort results into alphabetical order.
    local self_sorted = {}
    for key, _ in pairs(self) do
        if key:find('^test') then
            table.insert(self_sorted, key)
        end
    end
    table.sort(self_sorted)
    -- Add results to the results table.
    for _, value in ipairs(self_sorted) do
        result_table:insert_format(table_header .. "\n|-\n", value)
        self[value](self)
        result_table:insert("|}\n")
    end

    return (num_failures == 0 and "<span style=\"color:#008000\">'''Все тесты успешно пройдены.'''</span>" or "<span style=\"color:#800000\">'''" .. num_failures .. " тестов провалено.'''</span>") .. "\n\n" .. frame:preprocess(result_table:concat())
end

function UnitTester:new()
    local o = {}
    setmetatable(o, self)
    self.__index = self
    return o
end

local p = UnitTester:new()
function p.run_tests(frame) return p:run(frame) end
return p